IOTA Meeting, Apple Valley, Calif., 2004 July 2-3
Great Meeting with Asteroidal Occultations Galore
Most of the Power Point Presentations are here
New Reductions of the Helga, Nanon, & Angelina occultations
Updated: 2004 September 7
The 2004 meeting of the International Occultation Timing Association held on Friday, July 2 and Saturday, July 3 at the Lewis Center in Apple Valley, California, was a huge success. The meeting was held at the Thunderbird Campus Theater of the Lewis Center for Education Research (LCER) at 20702 Thunderbird Rd., Apple Valley, CA 92307- 3322 in the south-central Mojave Desert about 35 miles north of San Bernardino, easily reached from Ontario airport. Maps locating the center are here. This is updated from the September 2nd version to add Richard Nugent's minutes of the meeting and to replace Walter Morgan's "Plotting Updated Paths" paper with a corrected version that he supplied recently. Below is a list of observers who attended the meeting at the Lewis Center and/or tried to observe at least one of the five asteroidal occultations. Preceding the name I've put columns for the 5 California asteroidal occultations, "30" for the June 30th Helga event, "1" for July 1 Nanon, "3" for July 3 Angelina, "5" for July 5 Fidelio, and "6" for July 6 Carina. A "+" means that the occultation was observed, a "-" that the star was monitored but that no occultation occurred, "?" that a recording of the target star was made, but it was faint so that closer analysis of the tape will be needed to see if an event occurred or not (or I don't know what the status of the observation is), and "x" that the observation was attempted, but failed due to clouds or other reasons. 30 1 3 5 6 x - + Frank Anet - Martin Bonadio (Ariz., not at meeting) x - ? - Derek Breit + Bob Cadmus (Iowa, not at meeting) + John Centala (Iowa, not at meeting) - Steve Dodder (Arizona, not at meeting) + + - David Dunham ? Steve Edberg (Calif., not at meeting) + Joe Eitter (Iowa, not at meeting) Daniel Falla + Sam Herchak (Arizona, not at meeting) + Erik Hubl (Nebraska, not at meeting) - - - Bob Jones Lampert Levy - + - Art Lucas Gene Lucas + - ? Greg Lyzenga + - + Paul Maley - John Matthews (Ariz., not at meeting) Ralph Megna - - Dave Meyer - Ed Morana (Calif., not at meeting) ? Charles Morris (Calif., not at meeting) + + x Walter Morgan x - + x Richard Nolthenius + + - Richard Nugent x + - Derald Nye + David Oesper (with Eitter, not at meeting) - Randy Peterson + - Harold Povenmire (with Nugent) ? Steve Preston (with Breit) + Hank Sielski (with Dunham) Norm Sperling - Jim Stamm (Arizona, not at meeting) + Don Stockbauer + - + x Jim Stoffaire Bill Walsh - - x Wayne & Martha Warren Gary Witt - Karen Young (Calif., not at meeting) __________________________________ For details of the occultations, showing overview maps of the region showing all five paths together, click here. It includes almost final information about the observations of the June 30th Helga and July 1st Nanon occultations, and first results for the July 3rd Angelina occultation that prove the E-class asteroid has a high albedo and rather small diameter. Little or no information will be posted about the July 5th Fidelio occultation since I don't know of any positive observations of that event; an account is given of the single observation of the July 6th Carina occultation, and my ill-fated attempt to record it from 4 separate locations. Below is the agenda for the IOTA meeting, including plans for meeting before the occultations to plan for them. I've included below my Power Point presentations, and encourage the other authors to supply their presentations so I can post them here as well. During the next couple of months, I want to replace these with papers (Word or pdf versions) that will be published in a Proceedings issue of Occultation Newsletter. - All dates and times below are PDT = UT - 7h THIS WAS UPDATED JULY 9 JUNE 29 - Tuesday 6:00 pm Meet for dinner & last plans for Helga, in lobby of Howard Johnson's in Victorville. JUNE 30 - Wednesday 0:07 am (522) Helga occulted 10.8-mag. TYC 6310-01494-1, s. San Joaquin Valley, n. Mojave Desert, Las Vegas (and earlier east to Nebraska and Iowa). Click here for a nearly final sky plane view. The formal solution tried to give a minor axis of only 58 km, which just didn't look right, so I fixed that at 70 km for the solution shown. The observations show clear departures from an elliptical shape. Click here for a list of the observations entered so far (in Occult .OBS file form, a plain ASCII text file); if your observations are not included, or are in error, please let me know. 6:00 pm Meet lobby of Ramada Inn for dinner, Helga results 8:00 pm Meet for last plans for Nanon occ'n, LCER, Thunderbird JULY 1 - Thursday 2:48.4 am (559) Nanon occulted 8.6-mag. SAO 161827, Orange County, Riverside, San Bernardino Mountains, s.e. Mojave Desert (and earlier east to n.Arizona and n. Minn.). Click here for a nearly final sky plane view A good elliptical fit was obtained by giving Station 2's (Stockbauer's) reappearance 0 weight, but the time of that event was determined accurately from frame analysis of a time-inserted copy of the video tape so there's no reason to doubt it; it shows that there is a valley or crater there. Click here for a list of the observations entered so far (in Occult .OBS file form, a plain ASCII text file); if your observations are not included, or are in error, please let me know. 6:00 pm Meet lobby of Ramada Inn for dinner, Nanon results JULY 2 - Friday 10:00 am IOTA meeting starts, LCER Thunderbird campus Introductions LCER - Dave Meyer (Web) IOTA & attendees David dunham & all Business Meeting Art Lucas, administrative and financial report Reports of other officers Richard Nugent, IOTA observer's manual status David Dunham, tax deductibility of Venus transit trips David Dunham, new/changed vice presidents? David Dunham, IOTA meeting proceedings Other business Richard Nugent, IOTA election IOTA history and the 2003 Dirk Brouwer award of the American Astronautical Society, David Dunham (18 megabytes) Venus transit (Web links, not power point files) Expedition to Springs, PA - D. Dunham (Web) Expeditions to San Antonio (1882 sites) & Mauritius, P. Maley (Web) Lunch at a nearby Mexican restaurant Asteroidal Occultations Prediction methods The prediction process, S. Preston (pdf, 31 kilobytes) - proposal to change main IOTA web site in 2005 Prediction accuracy study, D. Dunham (289 kilobytes) Plotting updated paths, W. Morgan (Word, 1.8 megabytes) Observing methods & effects Fresnel diffraction effects, F. Anet Modern methods of observation, Gene Lucas (6.9 megabytes) 5:00 pm - adjourn for the day 6:00 pm Nearby Chinese restaurant for dinner 8:00 pm Meet for last plans for Angelina occ'n, LCER, Thunderbird JULY 3 - Saturday 4:19.1 am (64) Angelina occulted 11.9-mag. TYC 1215-01306-1, San Fernando, Bakersfield, n. Mojave Desert, Las Vegas Click here for a first sky plane view. The observations give dimensions of 48 by 53 km for this asteroid, in spite of the 97 km diameter given in the predictions. Paul Maley's well-timed chord at station 5 shows that the asteroid is probably bent, like Eros and Varsavia. Angelina was not observed by IRAS, so there was no previously-observed diameter for it. In those cases, the predictions use the absolute magniutude of the asteroid, assumning that it has a low albedo (low reflectance) similar to typical C-class asteroids (which seem to be carbonaceous and are darker than coal). But we should have checked the class of Angelina, which is E, like 44 Nysa, which has a high albedo and, consequently, relatively small diameter. Our observations proved the same for Angelina. Click here for a list of the observations entered so far (in Occult .OBS file form, a plain ASCII text file); if your observations are not included, or are in error, please let me know. I still need reports from Richard Nolthenius and D. Breit/S. Preston, and it would be useful to refine the times from the two southernmost tapes by D. Dunham/H. Sielski and W. Morgan (stations 8 and 9). 10:00 am IOTA meeting resumes, LCER Thunderbird campus Asteroidal Occultations (continued) Observing methods & effects Video time insertion - WWV, Manly inserter, D. Nye & J. Stoffaire GPS video time insertion - STVastro, A. Lucas GPS video time insertion - Kiwi GPS OSD, S. Preston A robust portable system - R. Nugent (Web) with Dunham's additional notes (Web) and Important caution about Sharp camcorders (Web) (these are all Web links, not power point files) Running remote stations - D. Dunham (14 megabytes) Random asteroid satellite search - P. Maley (1.5 megabytes) Strategy for observing asteroidal satellite occultations - A. Lucas, 362 kilobytes Portable 12-volt power - W. Morgan (Word, 1.1 megabytes) Attempting asteroidal occultations in Japan - P. Maley (432 kilobytes) Plans for tonight's Angelina occultation - 222 kilobytes Lunar Occultations during total lunar eclipses Zubenelgenubi, 1985 & 2004 - D. Dunham (Web, not power point) Plans for Oct. 27th eclipse graze - W. Morgan (Word, 773 kilobytes) Solar Eclipses NASA grant for analysis status & plans, D. Dunham (69 kilobytes) The FY 2004 funds for this were received at APL on July 9 Plans for 2005/2006 solar eclipses, P. Maley (622 kilobytes) See also This Web Site Details for the 2005 October Spain option (Not on web; 2.0 megabytes) Angelina occultation preliminary reports, all Lunch at nearby Chinese restaurant Asteroidal Occultation Results - D. Dunham, 2.4 megabytes Project to update all observations & include in Occult 2003 July Varsavia results & lessons learned 2003 August Bertholda success in Europe, new #2 event Some other 2003 & 2004 results - Tanette duplicity, etc. 2004 June Princetonia failure & Clarissa success lessons learned Predictions (1.4 megabytes) 2004 lunar occultations and grazes Jupiter partial occultation in December 2005 lunar occultations and grazes Antares and Spica 2004 future asteroidal occultations Plans for Fidelio, July 5 Plans for Carina, July 6 Other events, including - Aug. 24, Titan in n.e. Brazil - Sept. 5, Camilla - P. Maley, 5 min. - Sept. 12, Palisana (rather bright double star) - Oct. 11, Eros - Oct. 29, Flora - bright occultations by small asteroids 2005 asteroidal occultations, D. Dunham later events, such as 2010 March occ'n of Regulus Videos Roger Venable's (98) Ianthe May 16th two occultations recording videos of Helga, Nanon, & Angelina occultations videos of other asteroidal and grazing occultations 7:20 pm - adjourn meeting 8:00 pm Dinner at Marie Callendar's restaurant JULY 4 - Sunday - free JULY 5 - Monday 1:53 am (524) Fidelio occulted 10.9-mag. TYC 6913-00447-1, Santa Rosa, Sacramento, Reno, Salt Lake City (and earlier east to s. Wyoming, S. Dakota, & n. Minn.), but nobody obtained any observations of the occultation. JULY 6 - Tuesday 4:28 am (491) Carina occulted 9.9-mag. TYC 0483-01460-1, San Diego, El Centro, Yuma, Phoenix, central New Mexico (but this shifted north to San Bernardino, CA & Payson, AZ) I claim a record for stations deployed by one observer. One of my unattended telescopes was taken and recovered; an account of this effort, with thoughts on safely setting up remote stations, is here. David Dunham